I?ve been testing this guitar and I have no doubts about this one.
Still I do not know which model it is as there?s no sticker in it...
(Suppose that it?s one of the lower models.)
The seller says that it has VH-1 PUs and that it must have been made before -86.

So far so good.

I?ve also been offered a guitar - that is said to be as RSA100* with nitro and VH-1 PUs - by another seller. (* Made about 1990 I?ve been told)

The problem is that neither me nor this seller have seen the guitar IRL yet as it is shipping from Japan right now.

Here are the pics:

I have no reason not to trust the seller (I?ve bought guitars from him before) but I might loose the red one above while waiting for this one.

The sticker in this one seems to say RSA100 but the "plain" headstock just looks cheap to me...
Not something I?d expect from a higher model vintage Japanese guitar.

(So many fake Chinese guitars around these days...)

I bet that the seller will be able to tell if it?s the real deal as soon as he lays his hands on it, but right now I?m not totally convinced...